Development and application of kinetic methods, including a constant-ratio alternative substrate approach for differentiating enzyme mechanisms, an improved procedure for deriving steady state and isotope exchange equations, and application of these methods to the study of the flip-flop model of E. coli alkaline phosphatase and the reaction mechanism of rat liver phenylalanine hydroxylase. Purification and characterization of two key enzymes in the cascade control system of E. coli glutamine synthetase, the uridylyl-transferase and the uridylyl-removing enzyme. Other projects to be pursued: interactions of cyclic nucleotide phosphodiesterase, its protein modulator, and the modulator binding protein; theoretical and experimental studies of multiple inhibition in enzyme-catalyzed multisubstrate reactions. BIBLIOGRAPHIC REFERENCE: Bale, J., and Huang, C.Y.: Mechanism of E. coli Alkaline Phosphatase: Kinetic Evidence Contrary to the Flip-Flop Model. Fed. Proc. 36, 635, 1977.